Burglar alarm



Patented Apr. 12, 1927.

. i renne THOMAS E. OCONNOR, OF MINNEAPQLIS, MINNESOTA.

BURGLAR ALARM.

Application filed November 28, 1924.

My invention has for its object to provide an extremely simple andhighly eiiicient burglar alarm intended tor general use but especiallyadapted to be installed in buildings of various different types anddesigned to be actuated by the movement of a door, window, loose step orthe like.

To the above end, generally stated, the invent-ion consists ot the noveldevices ant combinations ot devices hereinalter described and defined inthe claim.

ln the accompanying drawings, which illustrate the invention, likecharacters indicate like parts throughout the several views.

Referring to the drawings:

Fig. 1 is a Jfragmentary view showing` the inside of a room having aninwardly swinging entrance door and a window eon'iprising upper andlower sliding sash;

Fig. 2 is a fragmentary view of the trip mechanism as applied to thedoor and its frame casing, on an enlarged scale;

Fig. 3 is a detail view with some parts. sectioned on the line 3-3 otFig. 2;

Fig. 4 is a detail view with some parts sectioned on the line 4 4 otFig. 2, on an enlarged scale;

Fig. 5 is a detail view with some parts sectioned on the line 5--5 ofFig. 1, on an enlarged scale;

Fig. 6 is a detail view with some parts sectioned on the line 6-6 ofFig. 5; and

Fig. 7 is a wiring diagram and the trip mechanism for the door and itsframe casing.

For the purpose of showing the invention applied in working order, thereis illustrated in the drawings a room S having an entrance door 9 hingedtor horizontal inward swinging movement in a door frame having a cas ing10. The room is also provided with a window comprising upper and lowersashes 11 and 12, respectively, slidably mounted in a frame having acasing 13.

Referring now in detail to the invention, the numeral 14 includes atranstormer the primary coil of which is in a primary circuit 15, andthe secondary coil of which is in a secondary circuit 16. Both of thesecircuits 15 and 16 are normally open and have interposed therein adouble knife switch 17 for simultaneouslyY opening and closing` saidcircuits. Interposed in the primary circuit 15 is a socket 18 in whichis secured a plug 19 connected by a lamp or duplex cord 20 to a plug 21secured in a socket 22 in a sun- `ply 01 lamp circuit 23 leading fromany suit- Seral No. 752,601.

28 in the iront of the casing 27 so that the light from said bulb willshine therethrough. The bell 26 may be located at any distant pointsomewhere outside oit the room 8. The socket 22, as shown, is secured tothe ceiling ot the room 8 and the Vsocket 18 is mounted on the left handend of the casing'27. The switch 17, as previously stated, is open andmay be closed by trip mechanisms, one of which is arranged to operate bythe opening `movement of the door 9 and the other ot which is arrangedto operate by the raising movement ot' the lower window sash 12.

The trip mechanism actuated by the door includes a pivoted flathorizontal finger 28, a depending' pivoted latch 29 which supports thefree end of said finger, a weight 30 supported on the finger 28, and asliding bolt 31 arranged to be projected back oit' the latch 29. Saidfing-er 23 is pivoted to a back plate 32 for downward swinging movementand the latch 29 is pivoted to said plate tor swinging movement in thedirection ot the opening movement of the door 9. The back plate 32 issecured to the casing 10 and the sliding bolt 31 is secured to the door9. The latch 29 is provided with an inturned lug 33 at its free end onwhich rests the tree end of the linger 23. The weight 30 is held in anopen ended guide 311 on the back plate 32 and is connected by a cable 35to the knife switch 1'? and runs over a guide sheave 36.

ln case the doer 9 is opened when the slid ing bolt 31 projects back etthe latch 29, said latch will be swung by said bolt in the samedirection as the opening movement of the door and thereby carry itssupporting` lug from under the linger 23 and allow the same to dropunder the action ot the weight 30 and release said weight. As the weight30 drops, it draws on the cable 35 and closes the switch 17. and hencethe circuits 15 and 16 thereby lighting the lamp 241, as a visual alarm.and ringing the bells 25 and 26, as audible alarms.

The mechanism ttor actuating the alarm in case the lower sash. l2 of thewindow is: raised, is substantially the same as that just described andincludes a pivoted iiat horizontal finger 37, a depending pivoted latch38 which supports the free end ot' said linger, a weight 39 supported onthe linger 37 and a sliding bolt et() having a laterally bent end 4 1arranged to engage a lug 42 on the latch 38 in case the lower sash l2 israised. Said linger 37 and latch S38 are pivoted to a baci; pla-te 43secured. to the casing 13, and

the sliding bolt l() is secured to the top rail of the lower window sashl2. The weight 39 is mounted within an open ended guide 44; secured tothe back plate stl. The latch 38 is provided with an inturned lug 45 onwhich the free end ot the linger 3T rests. The weight 39 is secured tothe cable by a cable i6 which runs over a guide slieave 47 on the casinglil.

Obviously, it' the lower sash 12 was raised only a very little, thelaterally bent end etl ot the bolt d() will engage the lugl and cam thelatch 38 outward sufficiently to carry its lug lo from under the finger3T and allow the same to drop under the action ot' the weigl'it 39. Asthe weight 39 drops, it draws on the cords Llo and and closes the switchi7, and hence the circuits l5 and 16, thereby light-ing the lamp 2li, asa visual. alarm, and ringing the bells 2:5 and 26, as audible alarms. Byretracting the sliding bolt 40, the lower sash l2 may be raised orlowered without actuating t-he alarm.

To permit the occupant oi' the room 8 to open the door 9 from theoutside without actuating the alarm, or leave the room and thereafterset the mechanism to be actuated by the door in case it is opened, thereis eX- tended through said door 9 a short shalt a8 having on its innerend a radially extended finger 4:9 for sliding the bolt 31. This lingerLi9 projects through an aperture in the bolt 3l with freedom ttorangular movement in respect thereto. On the outer end of the shaft 48,is a knob 5() by which said shai't may be turned to operate the slidingbolt 3l. To prevent the knob 50 from being actuated by an unauthorizedperson the same is mounted in a cover-equipped box 5l set into the outertace et the door 9 and has a bearing sleeve in which the shait 48 isturn-ably mounted. The cover oi the box 5l is secured in position by aVlug 53 arranged to interlock with said box and a hey-actuated lock 5l.)L linger piece 55 on the sliding bolt l0 will prevent the same fromturning at the time its laterally bent end il engages the lug 42. Topermit the switch .l'i' to be opened when resetting the trip mecha*nism, the casing 2T provided at its top with a lock-equipped cover 5Glocated directly over said switch, see Fig. 5.

It is, oif course, understood thatany desired number et doors or windowsmay be equipped with mechanism for actuating the alarm. It desired thealarm may be actuated by a mechanism operated by the deprcssion ot aloose step.

that I claim is:

'.l`he con'ibination with an element to be tripped and a tripping`member applicable to a door or window ot' tripping mechanism for theelement including a support hinged for swinging movement in a verticalplane, a latch releasably holding the support in a horizontal. positionand extending in the path ot' movement ot the tripping member, a weightloosely resting -on the support, and a connection lfroin the weight tothe element to trip said element when said latch is operated bythetripping element to release said support and drop the weight therefrom.

ln testimony whereotI I atix my signature,

